Synthetic resin



Y bonds of both the pinene and the abietic acid.

Patented Mar. 2, 1937 UNITED STATES SYNTHETIC RESIN Irvin w. Humphrey,Wilmington, per, assignor to Hercules Powder Company, Wilmington, Del.,a corporation of Delaware No Drawing. Application January 12, 1935,

Serial No. 1,501

17 Claims. (01. 260-8) This invention relates to a new composition ofmatter and method for its production.

In accordance with this invention a novel synthetic resin, havingcharacteristics rendering it valuable for use variously in thecommercial arts, is prepared by reacting together a pinene, such asalpha-pinene, beta-pinene, etc., or a mixture thereof, maleic anhydrideand rosin or abietic acid.. The reaction involved is probably explainedon the basis .of the unsaturated bond of the maleic anhydride reactingwith the unsaturated In preparing the synthetic resin in accordance withmy invention the reagents may be reacted in widely varying proportionsdepending upon the physical characteristics desired for the resinproduct with consideration to the use to which it is to be put.Generally speaking, it is desirable to employ maleic anhydrideapproximately in the proportion necessary to satisfy the reactivity ofthe pinene and the abietic acid with maleic anhydride. Thus, forexample, with use of relatively large amounts of pinene, the product issoft and tough, with more abietic in proportion to pinene, the productis hard and brittle and so on, it being clear that by varying theproportions and amounts of the reagents products having varyingcharacteristics may be produced. As illustrative, for example, a pinene,such as alphaor beta-pinene may be used within the range 0.1 to 0.9moles, maleic anhydride within about the range 0.2 to 2.0 moles andabietic acid within about the range 0.1 to 0.9 moles.

The pinenes are terpene hydrocarbons possessing no conjugated system ofunsaturated double bonds. Alpha-pinene is the principal constituent ofturpentine and boils at about 153-457 C. It may be obtained byfractionation of turpentine. Beta-pinene (b. p. about 162-168 C.) occursin French and other turpentines and may be obtained by fractionation ofthis material. As equivalents for the pure hydrocarbons, terpene cutsrelatively rich in the hydrocarbons may be used. Thus, a terpene cutboiling within about the range Eli-165 C. will be relatively rich inalphapinene. A terpene cut boiling within the range '160-170 C. may berelatively rich in beta-pinene, while perhaps also containing somealpha-pinene.

Such terpene cuts will contain various other reactive terpenes andimpurities, which, however, will not interfere in carrying out theprocess. of this invention, and which can be readily separated from thefinal product if non-reactive.

In preparing the improved synthetic resin the reagents will be reactedin the presence of heat. However, it will be expressly understood thatany means for effecting the reaction isjcontemplated as within the scopeof this invention. Any suitable temperature maybe used, though atemperature within the range (say) about -250 C. is desirable. Thereaction will usually be carried out under atmospheric pressure, butwith variations of temperature procedure under reduced or super pressurewill obviously be within the scope of my invention. The production ofthe resin in accordance with this invention may be carried out in anysuitable apparatus, as any suitable container in which the reagents maybe heated. On completion of the reaction any volatile unreacted mattermay be removed or separated from the product by the application of avacuum to the reaction mass before cooling. The reactants may be allmixed and heated to reaction temperature together, or the molten maleicanhydride may be added to the hot pinene-rosin mixture, or vice versa.If desired, partial reaction between the maleic anhydride and either thepinene or rosin may first be effected, and the remaining ingredientadded subsequently.

As a specific illustration, for example, 100 parts by weight ofalpha-pinene, parts of abietic acid and 98 parts of maleic anhydride areheated together at a temperature of approximately 200. C. for about 3hours. The pressure on the reaction mass is then reduced to about 15 mm.of mercury and any unreacted maleic anhydride and the inert ingredientsassociated with the excess pinene are distilled off.

The reaction product obtained by the above procedure will be found tohave a direct acid number of about 250, saponification value of about370, melting point (drop method) of about 85 C. and a rhodanometriciodine value of about 25. 'The acid and saponification values as well asmelting point and rhodanometric iodine value will vary considerably,depending upon the relative proportions of pinene to rosin, etc., alsoupon temperatures-and pressures employed when removing any unreactedmaterial after the reaction.

As illustrative of various amounts of the several reagents which may bereacted to produce resins in accordance with this invention, forexample, the reagents may be reacted in the various proportions given inthe following table:

' Alphaor beta- Maleic anhypinene Basin dride Parts by weight Parts byweight Parts by weight 188 20 v 98 42 98 150 83 98 .50 250 98 Theaboveproportions of rosin and maleic anhydride may also be keptconstant, while in-' creasing the proportion of pinene over that shownabove.

The several reagents in, for example, the pro- 45 and .vamishes.

portion given in the above table may be reacted in any suitablecontainer, at a temperature (say) within the range 175.C.-250 C. for(say) one to five hours. Volatile unreacted matter 5 may, as has beenindicated, be removed on completion of the reaction by reducing thepressure and, if desired, increasing the temperature in the reactionmass.

In place of pinene and rosin as separate ingredients of the reactionmixture, the crude oleoresin exuded from the living pine tree may betreated directly with maleic anhydride. Thus, for example, 102 parts ofoleo-rosin and 45 parts of maleic anhydride may be heated to 180 C.-190C. for about 3 hours to give a. highly acidic, resinous product. Also,the crude extract of terpenes from pine wood may be used, preferablyafter removal of the solvent employed in extraction. These crudemixtures of 20 rosin, pinenes, pine oil, and various other terpenecompounds may be heated, usually at about 150-250 C., with maleicanhydride in the proportion of about 0.8 mol. maleic anhydride per mol.of total. terpene compounds present for from two to eight hours. Thenon-reacted material is then distilled off, leaving a highly acidicresinous product.

The product in accordance with this invention will be found to be ahighly acidic resin, capable, for example, of reacting with alcohols,as, for

example, polyhydric alcohols, as glycerol, aliphatic glycols, etc., toyield synthetic gums or resins which have characteristics making themhighly desirable for use, for example, in varnishes, lacquers, etc. Asan example of the esterification of the product obtained in the specificillustration above with a polyhydric alcohol the following is illustrative: About 100 parts by weight of the above reaction product and 58parts of glycerol may be heated at a temperature of 210 C. for 6 hours.

The resulting resin has an acid value of and a melting point (dropmethod) of approximately 55 C. It is highly desirable for use inlacquers Drying or semi-drying oils or their acids may be added.

Esterification with monohydric alcohols as methyl, ethyl, butylalcohols, etc., may likewise be carried out, in the case of low-boilingalcohols preferably under pressure.

It will be understood that in producing the compositions comprising thisinvention abietic acid as such may be used or rosin, either .wood orgum, preferably high in abietic acid content may be used equivalently.The rosin may have been previously isomerized as by heat-treating orcontacting with acids which induce isomerization.

It is also contemplated to use other com-- esterified. Suitable estersare those from any monohydric or polyhydric alcohol such as methyl,ethyl, propyl, butyl, horny} alcohol, etc.,

abietanol, stearol, glycol, or glycerol, etc. Other compounds containingthe abietyl radical, such as abietyl alcohol, the various abietenescontained in rosin oil, etc., may be used in accordance with thisinvention, in place of abietic 'acid. When abietyl alcohol is used, theresulting resin will contain free hydroxyl groups which may beesterified with organic acids 35,191. example,

phthalic, abieticphydrogenated abietic, acetic,

succinic, drying oil fatty acids, stearic acid, etc. As a specificillustration, for example, of the use of an ester of abietic acid, partsby weight of alpha-pinene, 158 parts of methyl abietate and 98 parts ofmaleic anhydride are heated together with a temperature of about 200 C.for three hours. The pressure is then reduced to 15 mm. of mercury andthe excess of maleic anhydride and the inert ingredients associated withthe pinene are removed.

The acidic resin herein disclosed or its esters may be hydrogenated ifit is desired to saturate any double bonds which remain. The product maybe contacted with hydrogen under about 5-500 atmospheres pressure with ahydrogenation catalyst such as activated platinum, pal ladium, nickel,cobalt, copper-nickel, copperchromite, etc'. With a precious metalcatalyst, temperatures below C. will be normally used, the product beingdissolved in a suitable solvent. In using a base metal catalyst thereactants will he usually heated at a temperature of about l50-250 C.Thus, for example, 200 parts of the alpha-pinene-rosin-maleic anhydridecondensate described above may be hydrogenated by agitating it with 5parts of an activated nickel catalyst, at a temperature of 180- 200 C.for two hours under 200 atmospheres hydrogen pressure.

It will also be understood that maleic acid is contemplated as anoperable equivalent of maleic anhydride in the reaction within the scopeof.

this invention and within the purview of the claims hereinafter setforth. The use of maleicanhydride, however, is distinctly preferred.

This application is a continuation in part of my application Serial No.688,988, filed September 11, l933,'now Patent 1,993,036.

WhatI claim and desire to protect by Letters Patent is:

1. A synthetic resin comprising a reaction product of an alcohol and anacidic composition comprising a reaction product of the reaction ofapinene, maleic anhydride and a compound containing the abietyl radical.

2.. A synthetic resin comprising a reaction product of an' alcohol andan acidic composition comprising a reaction product of the reaction of apinene, maleic anhydride and abietic acid.,

8. A synthetic resin comprising a reaction product of an alcohol and anacidic composition comprising a reaction product of the reaction of apinene, maleic anhydride and an abietic acid ester.

4. A synthetic resin comprising a reaction product of an alcohol and anacidic composition comprising areaction product of the reaction of apinene, maleic anhydride and rosin.

5. A synthetic resin comprising a reaction product of a polyhydricalcohol and an acidic composition comprising a reaction product of thereaction of a pinene, maleic anhydride and a compound containing theabietyl radical.

6. A synthetic resin comprising a reaction product of a monohydricalcohol and an acidic comtaining the abietyl radical.

8. Asynthetic resin comprising a reaction product ofan aliphatic glycoland an acidic composition comprising a reactionproduct'of the reactionof a pinene, maleic anhydride and a compound contaning the abietylradical.

9. A synthetic resin comprising a reaction product of ethyl alcohol andan acidic composition comprising a reaction product of the reaction 0! apinene, maleic anhydride and a compound containing the abietyl radical.

10. A synthetic resin produced by combining a polyhydric alcohol, adrying oil fatty acid, and a reaction product formed by combining apinene, maleic anhydride and a compound containing the abietyl radical.

11. A synthetic resin comprising a reaction v comprising a reactionproduct of the reaction of alpha-pinene, maleic anhydride and a compoundcontaining the abietyl radical.

12. A synthetic resin comprising a; reaction product of an alcohol andan acidic composition comprising a reaction product of the reaction ofbeta-pinene, maleic anhydride and a compound formed from a pinene,maleic anhydride and a compound containig .the abietyl radical, and asolvent.

14. A coating composition comprising a reaction product or an alcoholand an acidic composition tormed from a pinene, maleic anhydride and acompound containing the abietyl radical;

a non-volatile lacquer ingredient and a solvent.

15 A coating composition comprising a reaction product of an alcohol andan acidic composition iormedirom a pinene, maieic anhydrlde and acompound containing the abietyl radical, a non-volatile varnishingredient and a solvent.

16. A synthetic resin comprising a reaction product of an alcohol and anacidic composition comprising a reaction product of the reaction of aterpene cut boiling within the range ".-165 C., maleic anhydride and acompound containing the abietyl radical. 17. A synthetic resincomprising a reaction product of an alcohol and an acidic compositioncomprising a reaction product of the reaction of a terpene cut boilingwithin the range -l70 C., maleic anhvdride and a compound containing theabietyl radical.

IRVIN W. HUMPHREY.

